Summary:A 21-year-old female underwent allogeneic bone marrow transplantation (ABMT) from her HLA matched brother for chronic myeloid leukaemia in the chronic phase. Four weeks post transplant she developed tenesmus, mucoid stool mixed with blood and lower abdominal pain. This rapidly progressed to greenish watery diarrhoea with flakes of mucous membrane floating in it, conforming to the classical clinical description of acute GVHD of the bowel. Stool microscopy showed profuse numbers of Blastocystis hominis, a parasite with doubtful pathogenicity in an immunocompetent host. In the present case the parasite played a pathogenic role as evidenced by the profuse number in the stool sample, focal neutrophil infiltration of the rectal mucosa, initial presentation of the patient with dysentery, and requirement for prolonged metronidazole therapy to eradicate the parasite and cure the diarrhoea. She also had grade I GVHD of the liver and skin. In developing tropical countries, hitherto unreported parasitic infestations may complicate the picture of acute GVHD. Keywords: acute GVHD; immunosuppression; Blastocystis hominis; pathogenic role Case reportA 21-year-old female was diagnosed as having chronic myeloid leukaemia in chronic phase. She had the Ph chromosome with a three-way translocation t(4,9,22). Her disease was initially controlled with hydroxyurea and she then started alpha interferon 3 mega units subcutaneously five times a week.One of her brothers was a complete HLA match, MLR non-reactive. She underwent allogeneic BMT from her brother after conditioning with the standard busulphan/cyclophosphamide regimen. She received

A young Arab woman with sickle cell-beta0-thalassemia disease developed acute colonic pseudo-obstruction that became chronic but showed some response to hydroxyurea. There was no evidence of microvascular or macrovascular occlusion. We also report the case of an Arab man with sickle cell anemia who presented with acute colonic pseudo-obstruction from which he recovered completely within a few days. Although the development of pseudo-obstruction in these two cases seems to have been a complication of sickle cell disease, its pathogenesis remains unclear. There are several reports of ischemic and inflammatory disorders of the colon complicating sickle cell disease; however, these two cases represent the first descriptions of large-bowel pseudo-obstruction in this hemoglobinopathy [corrected].